Neonicotinoids are Killing Our Insects (and Then Birds) Dead

Clothianidin is part of a class of systemic pesticides known as neonicotinoids, and they have been used widely across U.S. agriculture since the early to mid-1990s. “Systemic” refers to the fact that the pesticide pervades the plant it’s applied to entirely, and so any troublesome insect that takes a bite of any part, from root to leaf, will be poisoned.

“It is a serious ecological report rather than a book for general readers,” warns the website, but a serious ecological report is exactly what is required. Tennekes explains in this podcast that neonicotinoids are persistent in the environment in two ways: first, they can be active for months in plants they’re applied to, but more importantly, their neurological effects (a dérangement de tout les bee sens) may be irreversible.

Neonicotinoid insecticides act by causing virtually irreversible blockage of postsynaptic nicotinergic acetylcholine receptors (nAChRs) in the central nervous system of insects. The damage is cumulative, and with every exposure more receptors are blocked. In fact, there may not be a safe level of exposure.

That specific effect is what makes beekeepers nervous, because Colony Collapse Disorder (unlike other bee epidemics) doesn’t leave you with a hive full of dead bees; it leaves you with an empty hive. The disorientation that these pesticides provoke seems like a smoking gun, when also tied to a lack of grooming that would allow mites and funguses to flourish. Tennekes notes that if initial contact is not enough to kill (though it often is), the effects will accrete until the insect or earthworm bites the dust.

That dust is also compromised. Writes Tennekes: “The second catastrophic disadvantage of neonicotinoids is their potential to leach from soils. […] The excessive imidacloprid levels noted in surface water of western Dutch provinces with intensive agriculture have already been associated with insect decline and a dramatic decline of common grassland birds.” Birds, you’ll recall, feed on insects. If swaths of seemingly productive farmland are in fact food deserts, it’s Rachel Carson’s Silent Spring revisited, says Hennekes. (And U.S. bird population would not seem to be immune.)